Remote-control system



Feb. 1, 1949.

H. S. YOUNG REMOTE CONTROL SYSTEM Filed June 20, 1946 INVENTOR.

HZS'ATZOIZ/VEK Patented F eh. -I, 1949 UNITED STATES PATENT OFFICE i 7 2,460,337

R-EMGTE- UONTROL SYSTEM The Union Switch .& Signal Company, Swissv'ale, Pa, in 'cor'pora'tiono'fPennsylvania .Applicatio'fl June 20,1946, YSbi'iitl N0. 678,32 3

9 Claims.

which establishes this character for both steps,

and the fold capacity of the code ordinarily is not utilized.

It has been proposed heretofore to make use of .this fourth code condition (in which both steps have the one code character) to indicate a two position device. as shown, for example, in the copendlng applications for Letters Patent of the United States, Serial No. 649,072, filed February 20 1346 by Ira Cadman andSe-ria'l No. 665,018,

' filed April 26-, .1946 by Joseph A. Quinlan, both of Letters Patent of the United States No. 2,229,249,

granted to L. V. Lewis on January 21, 1941-, or that comprising amodification of the Lewispatent shown in an application for Letters Patent of the United States Serial No. 496,907, filed July 31, 1943, by A. P. J ackel for Remote control systems, which has since matured into U. S. Patent No. 2,411,375, granted Nov. 19, 1946 and assignecl to the-assignee of the present invention. The system of the Jackel patent is illustrated and :described inManual No. 506-A published October 1943 by the Union Switch & Signal Company.

Centralized traflic control systems usual-lyare 0 cates whether or not the switch is iockeiiin its reverse position. Thus when the switch-is locked in either its normal or its reverse position it provides one character for the codestep which indicates that the switch is locked'inthe corresponding position, and provides a difierent character for the other code step, thereby to provide an indication of either-one of two (normal and reverse) positions of the switch. -When the switch is unlocked by the switch machine, as when the switch points are in transit between extreme positions, the code intervals of the two switch indication steps b'othh'ave the different character mentioned, to indicate the third or transit condition of the switch. The two steps are capable of indicating a fourth condition i1 both have the one character referred t'o,but the switch obviously is not adapted to afford a control which applications are assigned to the assignee oi the present application. The present case is directed to subject matter similar to'that of the ;copending applications mentioned above;

It is an object of my invention to utilize the fourth condition provided by'the two steps of an indication code assigned to indicate a track switch. This fourth condition is employed 'to provideiniormation of the availability of power in the primary source for operating the switch. The fourth indication is provided when the switch occupies its normal position, "and is effective to permit both the position of the switch and: condition of the source to be indicated simultaneousiy, thusproviding full information to the operator of the condition of the apparatus at the switch.

Another object of my invention is to provide means for utilizing the two indication channels of a centralized traffic control system which indicate three conditions of a movable device, to provide an additional indication of the operation of a two-position device which otherwise would require'the provision of an additional code step.

A specific obiec't of :my invention is to provide means for enabling apparatus provided for indicating the condition of a remotely controlled power operated track switch to indicate also the condition of'the primary power supply for operating. the switch. Other -fe'a'ti-ir'es of my invention will be pointed out in detail in the accompanying specification.

{shall describe two forms of apparatus embodyi n'g my invention, and shall then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic view'illustra'ting one form of 'apparatus embodying my invention. Fig. 2 is a diagrammatic view of a modified form or the apparatus represented in Fig. 1, and also embodying my invention. In each of the two views, similar reference-characters refer to correspondinii parts. I

Referring to Fig; 1, a centralized trafflc control system is represented as comprising apparatus at an ofiice and at a station, and a communication system linking the oihce with the station.

The communication system, which may be of either the direct wire or the code system, is conventionally represented in the drawing as being a code system of the type illustrated in the previously mentioned Jackel patent and Manual 506-A. For the purposes of explaining the present invention it is sufiicient to state that the communication system provides a number of control channels (not represented in the drawing), and a number of indication channels some of which are represented in the drawing by dash lines, with the wires of each channel designated by reference characters which are the same as those used to designate corresponding wires in the Jackel patent. For example, the indication channels 49I39 and II4I represent individual code steps of an indication code, and the system functions in the manner explained in the Jackel patent so that if one terminal B of a suitable local source of current at the station is connected to wire I39 when an indication code is transmitted, the code will include a step of a particular character corresponding to the energization of channel 49 -439, to cause terminal B of a source at the office to be applied to terminal 49. If terminal B is not connected to line I39 when an indication code is transmitted, then the code will contain a step of a diiferent character corresponding to the deenergization of channel 49-I39 and terminal B at the oflice is not connected to wire 49. Similarly, if terminal B at the station is connected to wire I4! when an indication code is transmitted, the code will include a step of the particular character corresponding to the energization of channel 5I-I4I to apply terminal B at the ofiice to wire 5|, while if terminal B is disconnected from wire MI when a code is transmitted, a step of the different character is transmitted and terminal B is then not connected to code received from the station, as is explained in the Jackel patent, and a normal indication relay NWK and a reverse indication relay RWK selectively picked up according as energy is applied to terminal 49 or 5| at the oflice when the ofiice delivery relay D is picked up. After relay NWK or RWK is picked up, it is held energized over a stick circuit including its own front contact and a back contact of relay D, when that relay releases at the end of the indication code. To visually indicate the position of a track switch at the station, the office is provided with two indication lamps NWE and RWE. Lamp NWE is energized over front contact II of relay NWK, while lamp RWE is energized over a circuit including front contact I2 of relay RWK and back contact I3 of relay NWK, the arrangement being such that one lampmay be energized whenever its associated relay is picked up regardless. of the position of the other relay, but the other lamp may be energized only when its associated relay is picked up and the other relay is released. An additional indication lamp POE provided at the oifice when lighted indicates loss of the primary power supply at the station. Lamp POE is controlled over a circuit including 4 in series front contacts I3 and I2 of relays NWK and RWK, and is therefore energized when both relays NWK and RWK are energized.

The apparatus at the station includes a track switch W, a power switch operating mechanism SM operatively connected with the switch for operating it between its two extreme (normal and reverse) positions, and a primary source of power indicated conventionally in the drawing by the reference characters ac, connected to a "primary winding I5 of a transformer I6 having 1 its secondary winding I! connected to the input tain it fully charged. Connections from termiapparatus,'not shown but which may correspond to that shown in the Jackel patent, controlled by the communication system so as to establish control of the operation of switch W from the ofilce. Switch repeating relays N'WP and'RWP are provided at the station-to indicate the position of track switch W. These relays are selectively energized over a contact I9 operated by switch mechanism SM, provided switch W is locked in its normal or reverse position, respectively; The relays'NWP and RW'P govern the transmission of switch indication codes from the station to'the oflfice in the customary manner That is Ito say, relay NWP when picked up prepares a circuit for connecting terminal B at front contact 20 of relay NWP to wire I39; while relay RWP when picked up prepares a circuit for connecting terminal B at front contact 2| of relay RWP to wire MI. The connection of terminal B to wire I39 or I 4|, as the case may be, over the circuits just mentioned may include other contacts operated by apparatus shown in the Jackel patent but not shown herein because they are not necessary to an understanding of the present invention.

A power-offrelay POR is connected across primary winding I5 of transformer II; for indicating the'continuity of power from source ac and is held energized-as long as power is available from thealternating current source. Relay POR governs; in a manner to be explained hereinafter, the transmission of an indication controlling the power-off lamp POE at the ofllce. The provision of this' indication is of particular advantage in connection with a power operated track switch, because-in the event of a power failure itenables the operator to call the maintainer promptly, usually over the communication system, and .thereby facilitate the correction of thefault and restoration of the power supply before switch battery I8 is fully discharged. a

The indication codes are initiated at the station in the manner explained in the Jackel patent by the release of a normally energized station starting relayST corresponding to the similarly-designatedrelay in the application. Relay ST is normally held energized over a stick circ it-extending from terminal B at contact 22 of relay ST through the winding of relay ST and then over a front are. back contact of each of the several! indicating" relays. in series; to terminal 63;

the circuitas illustrated including frontcontact 23' of nelayROR, front contact: 2G1 of relay NWP, an'dzback COIIlJBLClJ Z-E of: relay.= but it i's to-be understood. that this. circuit includes additional contacts of other indication.relays such as shown inthe. JackeLpatent'.

The: condition: of; the apparatus; as shown; is that obtaining when: swi-tchoccupies1its nor=- mali position and power: is 2 available from sourceacat the statioia. At; the: office; normal; indica ti'on relayis energized over its stick circuit extending from terminal Batits frontcont'act' 26 over back contact 2-? ofrelay: D and the winding of relay NWK, tov terminal C; and normal switch indication: lamp =NWE is energized;over its circuit including:v frontv contact i i of: relay At the station, switch W'isiih it's n-ormal position;. normal switch repeatin relay is energized. over contact [9' operate'd'by switch-mechanism SM;- in its normalf position; and relays POR. and ST are energized;

The apparatus. at the station operates in the usualmanner to reflect a: change-in positioniof track switch W. For exampleif the s-witch'machine is controlled over. the communication system to cause switch? W' to:- operate' from its norv mal to-itsreverseposition; the initial movement of the mechanism as itunlocks the switchpoints to-permitthem to-be moved to the=-reverse:.position, results in openingicontact. l9 of'themechanism-in the circuit of relay: NWFw-hereupon' that relay releases. Front contact 24 of relay opens to interrupt the previously traced'stick" circuit of starting relay S'IX. RelayST is a quick acting relay and releases prior to the' closi'n-gof plained in the Jackel patent; Duringthe-trans mission of this code both relays NWP and RWP are in their released positions so that terminal B is applied to neither wire 13901: Mil. As a result, both switch indication channelsain' thiscode are deenergized and. when relayDpicks up atthe office, the stick circuit of relay is interrupted so that relay NWKreleases to open. its

front contact H and deenerg'ize lamp With both lamps NWE and RWE dark at the ofiice, an indication is provided of the. unlocked or transit condition of the switch; Atthe end of the complete indication: code initiated? by: the

release of relay NWP, relay ST liecomeseneri'zedin the manner explained in the Jackelipat ent by energy applied in a pick-up circuit; to wire- I [hand relay ST thereupon picks upsto closeit's contact 22 to complete its stick: circuit which holds that relay energized after. its pick-up cir cult becomes interrupted. The stick: circuit of relay ST now includes back contact. 24 0f: relay NWP and back contact 25 0i relay RWP, buledoes not include either the: front or back contact 23 of relay POR. In other words; with relay NWP released to close its back" contact. 2 relay-"FOR is removed from. control of the stick circuit. of relay ST.

When" the: switch rea ches: its reverse lockedfp'osi tion; relay RWP is. energized overcontact HY on mechanism SM- closed im the reverse locked posh- 6 tion of the switchi Elie pickihg-upofi'relay deenergizes relay to transmit an indie'a'xtiom code i'ndieatin g tliat -the switch i's-lock'ed I-BVGI'SG In this instance; wire M l is connected to== ter min-al B- cverfront contact II of: relay RWP so= that when rel'ay D- at' the ofli'ceis operated relay RWK piolse up over itSi circuitincluding front contact of relay D2 to: cause reverse switchindication lamp RWE to become lighted over front-contact I 2:- ot relayRWK 'and tacit contact I 'l ofi'relay ReIayRW-K is held energizecli in its stick; circuit including' its fiont- Contact" 31? an'd bac'le contactw of relay D} when the latten relay re1eases= followingthe transmission of the" complete indication code.

The apparatusfunctionsto indicate 1 operatiom of swit clr- W from its: reverse to its normal posi*-- tiomih a similarmanner; aswill bereadily urrder stood;

ltnowilie assumed that with theswitch locked normal so-that relay' ST is held energized ovenitsstick' circuit including front contact 23 of relay FOR} front contact 24 of" relay and liack contact 2l5of relay RWP', a failure of" the-A G1 power supply occurs; Due" t'o the loss switch ihdication channels of thein'dication codeare' energ-i'ze'd, the-one-ehannel 49 -l-'39"over front contact 26* of switch repeater relay'NWP; and the other channel 5 "|'--l'4l over a circuit including front contact '29 of relay NWP, back contact" 28; of relay PCB, and back contact 21 ofthedeen; ergi'zed switch repeater relay RWP. It" follows that if the alternating current source of powerv shouldifailwhen the switch'is' locked in its'normalposition, channels QBl39j and. 5|l'4"| are both energized so that both indication. relays NWK and RL'WK at the ofiice are picked up by the indication code, and a. circuit is closed" including front contact I'3' of relay NWK and front contact 12' of relay RWK'. f'orrindieation:

lamp POE which thereupon. becomes: lighted to" indicate a failure of power' at the station: Also, the circuit including front contact ll' 0i relay NWK is maintained for indication lamp- NWEwhi'ch reflects thenormalpositi'on ofswitch Wat: the station.

The relays NWK and" RWK are retained" ener=- gi'zedovertheirrespective stick circuits when relay" Df'releases following the completion of the: code which transmits the power-on indication. It is apparenttherefore that the power-off indi catiorrlampPOE and normal switch" indicationv lamp: will be maintained energized following receipt of the power-off indication; to i'ndi cate'failiire-of power-at'the switchloca-tiom an'd to indicate the position ofthe switch". Thesetwo indications will he maintained so long as theposi tion of the switch is not changed and the power failure-is not corrected? Upon correction of the' power" failure; relay FORE immediately picks upat the s-tatiorrtb 'open the sti'ck circuit of starting switch. and. causes the corresponding normal switch indication relay NWK at the ofilce to be energized and the other switch indication relay RWK-to be deenergized. The switch indication lamp NW E will be maintained energized, :but lamp POE becomes dark with only one indication relay picked up, so that the position of the switch is indicated while the power-off indication is cancelled to indicate restoration of power to the primary source.

It will next be assumed that a failure of the A. C. power occurs when the switch occupies a position other than its normal position, i. e, in either its reverse position or its intermediate position. In either of the latter cases, relay ST will be held energized over its stick circuit which includes back contact 24 of relay NWP, and in such event contact 23 of relay POR is removed from control of the stick circuit of relay ST so that a change in position of relay POR. has no effect upon the circuit of relay ST and a failure of power in, this instance does not cause any transmission of an indication code and does not affect the indications displayed at the oflice. Also, the restoration of power when the switch is out of its normal position will not aiTect the indications at the office because relay POR in picking up does not control the circuit for starting relay ST under the conditions assumed. It is, of course, obvious that the apparatus functions in the usual manner to indicate the transit or reverse position of the switch regardless of whether power is present or absent, because contact 25 of relay RWP is always effective to control the circuit of relay ST to initiate the transmission of an indication code upon a;

change in position of relay RWP. The codes initiated by relay RWP will energize wire MI when relay RWP is picked up to close its front contact 2 l, but'when relay RWP is released then terminal B is disconnected from wire ML, In any event, however, the operation of relay RWP will not cause both channels to be energized even though relay POR is released to reflect absence of power,

stored when the switch is returned to its normal;

position, then the indication code transmitted by operation of relay NWP to its picked-up position results in the energization of channel 49-439 over front contact 29 of relay NWP, and channel 5l-!M over front contact 20 of relay NWP, back contact 23 of relay POR. and back contact 2! of relay RWP so that both switch indication channels become energized to cause the display of both the normal switch and power-off indications at the office. A restoration of the power when the switch is normal will of course be reflected at the office because the code initiated when relay POR picks up will have only a single energized step corresponding to channel 49l 39 and in such case relay RWK is released to open the circuit for lamp POE and cancel the power-01f indication displayed by that lamp.

In Fig. 2, I have represented the apparatus of Fig. l modified to incorporate the communication system of Lewis Patent No. 2,229, 49, in place of the system of the Jackel patent used in Fig.1."

trol jrelays NWK and RWK in the same manner as explained in connection with the apparatus of Fig. 1-. That is, relay NWK is energized over channel 93il3 whenever terminal B is connected to Wire 93 over front contact 20 of relay NWP during the transmission of an indication code; and relay RWK is energized over channel -4 l5 whenever terminal B is connected to wire 95 during an indication code, the connection of terminal B to wire 95 being effected when relay RWP is picked up, over a circuit including back contact 20 of relay NWP and front contact 2| of relay RWP. Terminal B may also be connectedto wire 95 when relay RWP is released, provided that'relay POR. is released with relay NWP picked up to complete a circuit from terminal B at back contact 3! of relay POR through front contact 32 of relay NWP to wire 95. It is to be seen, therefore, that wire 95 is energized during .an indication code when relay RWP is picked up to indicate that switch W occupies its reverse position, and also when relay POR is released to indicate a failure of power when switch W is in its normal position as indicated by relay NWP in its picked-up position. In the latter case, of course, wire 93 will also be energized over front contact 20 of relay'NWP so that when relay POR is released and relay NWP is picked up, an indication code transmitted will be effective to pick up both relays NWK and RWK at the oifice to cause a display of both the normal switch and power-off indications in the manner illustrated in Fig. 1.

A slow releasing repeater relay PORA is provided in Fig. 2 for relay PCB and is energized over an obvious circuit including front contact 3| of relay POR.

The station starting relay ST of Fig. 2 is of the normally deenergized type provided with a pick-up circuit completed upon a change of position of relay POR whenever relay NWP is picked up to indicate that switch W occupies its normal position. When relay POR releases with relay NWP picked up, a circuit is completed for 17-, relay ST, during the slow release interval of repeater relay PORA, this circuit extending from terminal B at front contact 34 of relay NWP, through front contact 35 of relay PORA, back contact 36 of relay PCB and the winding of relayST to terminal 0; while when relay POR picks up with relay NWP also picked up, then relay ST is provided with a circuit extending from terminal B at front contact 34 of relay NWP through back contact 35 of relay PORA,

front contact 36 of relay PCB and the winding of relay ST to terminal C. Relay ST when picked up closes its front contact 33 to initiate the transmission of an indication code in the manner explained in the Lewis patent, thereby establishing the channels 93-l l3 and 95l I5. A selector relay S is also operated by the code, which serves to release relay ST. The relays S and ST function like the similarly designated relays of the Lewis patent, and it is to be understood that the circuits for relay ST include additional branches, not shown herein, so that relay ST becomes energized in response to each change in the positions' of relays NWP and RWP.

The, apparatus of Fig. 2 functions to control the indication relays NWK and RWK (which in turn control indication lamps NWE, RWE and POE in the manner illustrated in Fig. 1) upon any change in position of the switch repeater relays NWP and RWP (in the manner explained in detail-in the Lewis patent) and upon any assess? amanner corresponding to that-described for "l, to indicate at the office the position of ob W, and to provide at the ofiice an indihati'o'n pertainingto the primary source bf power when the switch occupies its normal position.

My invention therefore provides a simple means for indicating loss'of power on the two code steps assigned to indicate the position of a switch. The invention requires the use of but a single relay POR, or alternately a relay POR and its repeater relay PGRA, which "effect the control of both the startingrelay and the poweroif indication when the switch occupies its-1101'- mal position. The operator is thus able to determine whether power from the A. C. source is available for operation of the switch by maintaining the switch in its normal position, or by restoring the switch to its normal position as soon as any movement over the switch in its reversed position has been completed. Inasmuch as the switch usually occupies its normal position and is'op'erated from that position to permit movement "of traffic over the switch in its reverse position only when such a movement becomes necessary and for only such a period as 'is' necessary to permit such a movement, the

power-off indication provided by my invention is efiective to provide adequate information to the operator relating tothe A. C. power source.

Although I have herein shown and described only two "forms of remote control apparatus embodying my invention, it is to be understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

a normal and an operated position, an ofiice, a

communication system linking said ofiice with said relays and including two indication channels,

indication means at said ofiice controlled by said two channels for distinctively indicating the three positions of said first device and the operated position of said third relay; and means controlled by said first and second relays for controlling said indication channels to cause said indication means selectively to reflect the positions of said first device and additionally controlled by said third relay when and only when said first relay is picked up for controlling said indication "channels to cause said indication means to indicate the position of said third relay aswell as the position of said first device.

2. in combination with a railwaytrack switch having two eatreme portions and enamel-mediate position; a" source or current for operating said Switch, a power os' relay f01' said source, a control office provided with a first indication meansfor indicating the position of said switch and asecond indication means-for indicatingthe condition" of said power-ofi re'lay, a communicahon system linking 's'aidofiice with said switch and provided withtwo indication channels over which code elements having one character or afibtfir" may b transmitted, means Controlled 10 by said switch'whe'n said power-off relay indicates presence of power in "said source for controlling saidcommunication system so'th'at the code ele-.

ment transmitted over one channel has one character or another depending upon whetl'ier or not said switch is in a first of "its said two extreme positions and that transmitted over the other channel has one character or another depending upon whether or not said switch is in the second of its said two extreme positions, means controlled by said power-oh relay when indicating absence of power in said source efieotive when and only when said switch occupies a selected one of its said two extreme positions for controlling-said communication system so that the elements transmitted over both of said channels have said one character, and means controlled by the character of the code elements transmitted over said channels for controlling only said first indication means when only one of said elements has said other character and controlling both said second indication means and said first indication means when both said elements have said one character.

3. In combination with a power operated railway track switch having two extreme positions and an intermediateposition, two indication relays at a control oiilce, a communication system linking said switch location with said oflice and providing two indication channels one for each indication relay over each of which code elements may be transmitted for energizing the associated indication relay, a source of power at said switch location, a power-off relay connected across said source and released upon failure of power, means for controlling said communicationsystem by said switch and said power-off relay so that when said power-oh relay is picked up one or the other of said two indication relays is energized over its channel according as said switch is in one or the other of its two extreme positions and when said power-oil relayisreleased both said indication relays are energized when and only when saidswitch occupies a selected one of its said two extreme positions, said indication relays each arranged so that when energized by a code element it remains energized until transmission of another code, and means at said ofiice controlled by said indication relays for indicating at all times the position of said switch and additionally eii ective to indicate the position of said power-off relay when said switch occupies its said selected one extreme position.

i. In combination with'a power operated railway track switch having a normal and a reverse and an intermediate position, a control office, a communication system linking said control oiiice with the switch location and providing two indica tion channels over each of which code elements having one character or another may be trans mitted, a source of power at said switch location for supplying energ for power operation of said switch, a power-off relay deriving its energization from said source of power, means for controlling said communication system by said switch when said power-off relay is picked up so that the code element transmitted over one channel has one character or the other depending upon whether or not said switch is in its normal position and that transmitted over the other channel has one character or the other depending upon whether or not said switch is in its reverse poSitiOi'l, means effective when and only when said switch is in its said normal position and said power-oh relay is 7 at said ofiice for reflecting the position of said sa d power-off relay, and means [or controllin first indication means at all times in accorc with the character of the code transmitted o-er said channels and for additionally controlling said second indication means when both said elements have said one character.

5. In combination with a power operated railway track switch having a normal and a reverse and an intermediate position, a control office, a communication system linking said control ofiice with the switch location and providing two indication channels over each of which code elements having one character or another may be transmitted, a source of power at said switch location for supplying energy for power operation of said switch, a power-off relay deriving its energizetion from said source of power, means for controlling said communication system by said switch when said power-off relay is picked up so that the code element transmitted over on channel has one character or the other depending upon whether or not said switch is in its normal posi tion and that transmitted over the other channel has one character or the other depending upon whether or not said switch is in its reverse posttion, means controlled by said DOW8F-OE relay if deenergized efiective when and only when said switch occupies its normal position for controlling said communication system so the elements transmitted over both of said channels have said one character, two indication relays at said oifice one for said one channel and the other for said other channel, each arranged to be energized when its associated channel transmits a code element of said one character and when. energized, retained energized until transmission of another code, two indication lamps one for each indication relay, means controlled by the said one indication relay when picked up for energ zing its associated lamp regardless of the poshtion of said other indication relay, means controlled by said other indication relay when pic zed up for energizing its associated indication lamp provided the said one indication relay is released, and a third indication lamp energized. whenever both of said indication relays are picked up.

6. In combination with a power operated railway track switch having a normal and a reverse and an intermediate position, a control ofiioe, a communication system linking said control office with the switch location and providing two inclication channels over each of which code elements having one character or another may be transmitted, a source of power at said switch location for supplying energy for power oper tion of said switch, a power-off relay deriving its energization from said source of power, means for controlling said communication system by said switch when in said normal position so that the code element transmitted over one channel has said one character and that transmitted over the other channel has said one character or the other depending upon whether or not said poweroff relay is released or picked up respectively, means for controlling said communication system by said switch when in said reverse position so that the code element transmitted over said other channel has said one character and that transmitted over said one channel has said other character, means controlled by said switch when iii in its said intermediate position for controlling said communication system so the elements transmitted over both of said channels have said other character, two indication relays at said office one for each of said channels and each arranged to be energized when its associated channel transmits a code element of said one character and when so energized retained energized until transmission of another code, two indication lamps one for each indication relay, means controlled by the one of said indication relays controlled by said one channel and effective when picked up for energizing its associated indication lamp regardless of the position of the other indication relay, means controlled by the other of said indication relays controlled by the said other channel and effective when picked up for energizing its associated lamp provided said one indication relay is released, and a third indication lamp energized whenever both of said indication relays are picked up.

7. In combination with a power operated railway track switch having a normal and a reverse and an intermediate position, a control ofiice, a communication system linking said control office with the switch location and providing two indiu tion channels over each of which code elements having one character or another may be trans mitted, a source of power at said switch location for supplying energy for power operation of said switch, a power-off relay deriving its energization from said source of power, means for controlling said communication system by said switch when in said normal position so that the code element transmitted over one channel has said one character and that transmitted over the other channel has said one character or the other depending upon whether or not said power-off relay is released or picked up respectively, means for controlling said communication system by said switch when in" said reverse position so that the code element transmitted over said other channel has said one character and that transmitted over said one channel has said other character, means controlled by said switch when in its said intermediate position for controlling said communication system so the elements transmitted over both of said channels have said other character, means at said ofiice for indicating the normal and reverse positions of said switch and controlled by the character of the code elements transmitted over said channels to indicate the normal switch position whenever a code element of said one character is transmitted over said one channel and to indicate the reverse position of said switch only when a code element of said one character is transmitted over said other channel and the code element transmitted over said one channel is of the other character, and means at said office for indicating the released position of said power-oif relay effective whenever the elements of both channels have said one character.

8. In combination with a power operated railway track switch having a normal and a reverse and an intermediate position, a normal and a reverse indication relay at a control oflice, a communication system linking said switch location with said oifice and providing two indication channels one for each indication relay over each of which code elements may be transmitted for energizing the associated indication relay, means for controlling said communication system by said switch so that the said normal or the said reverse indication relay is energized over its channel according as said switch is in its said normal or reverse position respectively and neither of said relays is energized over its corresponding channel when said switch is in its said intermediate position, a source of power at said switch location for supplying energy for power operation of said switch, a, power-oil relay connected across said source and released upon failure of power means for controlling said communication systern by said power-off relay when released effective only when said switch occupies its normal position so that both indication relays are energized over their corresponding channels, each of said indication relays being arranged so that when energized by a code element it remains energized until transmission of another code, a normal switch position indication means and a reverse switch position indication means and power-01f indication means at said office, and means controlled by said indication relays for energizing said normal switch position indication means whenever said normal indication relay is energized, and for energizing said reverse switch position indication means whenever said reverse indication relay is energized provided said normal indication relay is deenergized and for energizing said power-oil indication means whenever both c: said indication relays are energized,

9. In a remote control system, a first movable 14 device having a first and a second and an intermediate position, a first relay picked up only when said first device is in its said first position, a second relay picked up only when said first de vice is in its said second position, a third relay having a normal and an operated position, an ofiice, a communication system linking said oflice with said relays and including two indication channels, two indication relays at said office controlled respectively by said two channels, a starting relay at said switch location for establishing said indication channels operative upon any change of position of said first and second reand upon change of position of said third relay only when said first relay is picked up, means effective following operation of said starting relay for controlling said channels to pick up a first of said indication relays whenever said first relay is picked up ans. to pick up the second of said indication relays whenever said second relay is picked up or said third relay is in its operated position and said first relay is picked up, and means at said ofiice controlled by said indication relays for selectively indicating the position of said first device and also indicating the position of said third relay only when said first device is in its said first position.

HENRY S. YOUNG.

No references cited. 

